*Figure 2.R2.1/2F(13/27B) and attached filaments. This view
corresponds to figure 2 in the entry for R2.C(1/2). The filament
that extends out of view to the left is R2F(1/2(13/27B1)B1) . In the
right-hand (ASCII
art) figure, the square shows the location of figure 3.